A semiconductor memory card having a NAND-type flash memory or the like built therein is being downsized while having larger capacity. In order to realize the reduction in cost of the semiconductor memory card, it has been studied to mount semiconductor chips such as a memory chip and a controller chip that constitute the semiconductor memory card on a lead frame having external connection terminals. On the lead frame, chip components such as a capacitor and a fuse, in addition to the semiconductor chips, are mounted. In the semiconductor memory card using the lead frame, the entire lead frame except surfaces of the external connection terminals is resin-sealed together with the semiconductor chips and the chip components.
When the lead frame is applied as a circuit substrate for the semiconductor memory card, there is a worry that a problem based on a structure of the lead frame arises. For example, the lead frame has a limitation in a formation of circuit compared with a wiring board, so that it may be difficult to form a circuit of the memory chip and the controller chip only by the lead frame and bonding wires. Further, although a thickness of the semiconductor memory card is specified by various standards, heights of the semiconductor chip and the chip component are not uniform, and the height of the chip component is generally higher than that of the semiconductor chip. When the lead frame is resin-sealed together with the semiconductor chips and the chip components under such a condition, a covering property of a sealing resin layer with respect to the chip components may be lowered, or a warpage of the semiconductor memory card and a positional displacement of the lead frame may occur at the time of performing resin sealing.